If JPMorgan CEO Jamie Dimon was trying to set off the bitcoin community with his criticism of cryptocurrency, he succeeded.On Tuesday, Dimon called bitcoin a "fraud," described it as "not a real thing" and said, "someone is going to get killed."Crypto enthusiasts took little time in firing back -- on Twitter and on TV. We emailed Fred Wilson, a partner at Union Square Ventures and one of the first investors in bitcoin-related start-ups, to get his thoughts on Dimon's comments."You have to have an open mind to be able to see the future," Wilson said.